Currently, some digital devices combine with a G-sensor (accelerometer) inside to sense acceleration changes. When a digital device is speeding up, the G-sensor converts a moving change such as shaking, falling, ascending, descending into an electrical signal, which will be calculated and analyzed by a microprocessor to accomplish intentional functions. For example, an MP3 device can change a currently playing song to a former or a later one according to a rocking direction by the user, or calculate the pace of the user when the MP3 device is in a pocket of the user. In addition, advanced notebook is generally equipped with a G-sensor for immediately protecting the hard disk thereof to avoid damages when sensing express acceleration (such as accidentally dropping). Since G-sensor is an intelligent gravity sensing system used in hard disk drives for detecting a current status, then in an event of unexpected falling, the hard disk can sense the acceleration and make the head thereof automatically reset and depart from its plate to avoid accidental impact on data transmitting process, which will interrupt normal data reading/writing operation.
On the other hand, G-sensor technology can also be applied in a mobile phone so that appropriate application software, such as gaming, video playing and camera can be implemented based on user actions via the G-sensor. Similar to Wi-Fi system, G-sensor is also a micro electromechanical system (MEMS: Micro Electromechanical System) in which micro-sensors, processors and signal processing and control circuits, interface circuits, communication and power are combined.
Nevertheless, a mobile phone within a built-in G-sensor has relatively single features in moving state, which bring inconvenience to the user for calling and reduce user experience sense. Furthermore, great damages definitely occur especially when the user's handheld apparatus falls into the water since there is rare protection imposed on handheld apparatus.